Sensitivities of our experiment to TBC (STBC ) and to substrate conductivity calculated according to Eq. (1) with the data recorded for a sample of 177 nm Al sputtered on an Ar:O plasma-treated diamond. Three main temperature regions can be distinguished for their behavior as a function of delay time.
Calibration tests of our equipment for three samples: 130 nm Al evaporated on Sapphire (circles) and simulation used for TBC extraction (continuous line); 130 nm Al evaporated on 100 nm thermal SiO2 on silicon (squares) and simulation (long dashed line); 177 nm Al sputtered on Ar:O2 plasma-treated diamond (diamonds, for comparison with calibration samples) and simulation (dashed line); 75 nm Al evaporated on HF-dipped Si (triangles) and simulation (dotted line). The spot size had an average diameter of 4.7 μm in every case. The thermophysical data not mentioned in the figure are k Al = 237 W m–1 K–1, C v , Al = 2.44 MJ m–3 K–1, , k Si = 142 W m−1 K−1, , k C = 1400 W m−1 K−1, .
Recorded XPS signal around the C s 1 peak of diamond as a function of sample surface treatment. (a) shows two examples of fitting using gaussian-lorentzian subpeaks for quantification and (b) shows the raw curves and their envelope fits.
TBC results obtained for Ar:O (circles) and Ar:H (diamonds) plasma-treated samples with aluminum. Data from Stoner and Maris 29 (filled circles) and Collins et al. 9 (filled triangles: oxygenated, filled squares: hydrogenated) are shown for comparison. The curves show simple limits and models for Al/diamond TBC: radiation limit (dashed-dotted curve), Diffuse Mismatch (dashed curve), and Acoustic Mismatch (dotted curve). Another limit called Maximum Transmission Model (not discussed in the text, see Ref. 33 ) that takes inelastic interactions into account is put in plain curve as the maximum value that can be expected. The parameters used for the curves are: .
Measured TBCs as a function of the diamond surface treatment and Al deposition technique. A typical standard deviation over 4 measurements is given after the values.
Proportions of the C s 1 subpeaks in the recorded XPS signals. Two measurements were taken in each case on 2 different diamonds.
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